Spark-plug.



B. BREWSTER.

SPARK PLUG.

APPLICATION HLED 1AN.14.1918.

Patented Feb. 11, 1919 w i 00 f/o ,i w w f fierefmxa. pi'mfde a spark ima when combustion is ("n's charge accnmuates The use end operation of a sparh plug is too well known and understood to require specific elueidntion here.

It is nssinned that the sperk will oceur progressively between the suceessive pair of balls in the Circle of terminale or elec- `trodes.

While I have herein shown a single embodimentof n13v invention ii is innifest that various changes and (lisposiiion of parts may be le Within the scope of the ap .ended cl Iaving d claim is:

15 1. A "spnrk plug comprising a Shell and un inclosed nsnhiting core; a centrally disposed electrical termi-'ml projeoting from one end of 'the eore;-zi partifeireular insulating wall projeeting from the core partlysurrounding said terminal n termin'l se- 'urel to the lower edge of the Shell and a. series of spaced-apnrt electrienlly-condncting hlies hetween said terminals outside of saiil well.

2. A sparh plug eomprisingr a shell and :i core; a eentrnlly ilisposed, globular, elecrrienl terminal projeetiingr from the inner em! of the, eore; a similar terminal secured to the inner end of the Shell; a Series of glohuhu' eleetrodes, l'upported on the core und urriulged iii spu'ced-apart circular sequenee nrouml the central terminal, and a pnrbcircuhu' wall, of insulating material, between the central terminal and said electrodes.

In. testimony whereof I hereunto set niy hand in the presence of two Subscribing witnesses.

ROBERT BREWSTER. 

